The Scubapro S-Tek Donut Wing is constructed of durable 1000D Cordura outer shell and 500D Cordura inner bladder. Improved rounded profile reduces air trapping. Wing features an elliptical EPDM corrugated inflator hose and Scubapro's K-Style Balanced Power Inflator (BPI). Scubapro BPI mechanism: Scubapro's BPI provides a high inflation speed, especially at depth. Inflator has different shaped inflation and purge buttons for easy use even in extremely low light or murky water conditions. Inflator is also equipped with a rapid pull dump mechanism with cable pull for easy deflation of the air bladder. Included with the inflator is a 3/8" threaded low-pressure hose for attachment to the first stage regulator. For trimming buoyancy when diving in an inverted position the donut wing has a left lower overpressure relief/pull dump valve with pull cord. The wing weighs 1.85 lbs. (840g).From the ManufacturerS-Tek Donut Wings offer BPW divers reliable buoyancy control regardless of their diving position. Their durable rounded profile allows for smooth, controlled air migration.